1. Field of the Invention
The present invention relates to a mounting plate to which a solid-state imaging device is attached, and a method for bonding the solid-state imaging device to the mounting plate.
2. Description of the Related Art
As is well known, a solid-state imaging device such as a CCD is used in a digital camera or a video camera. The solid-state imaging device is available as an electronic package, which is not usually directly mounted in the digital camera or video camera. This is because the solid-state imaging device needs to be placed at a proper position relative to a photographing optical system of the digital camera or video camera, and it is difficult to hold the solid-state imaging device at the proper position by itself (i.e., as a single body).
Therefore, conventionally, the solid-state imaging device is fixed on a mounting plate with an adhesive agent, and the mounting plate is then attached to an inner frame provided inside the digital camera or video camera, with a screw. The digital camera or video camera is usually designed in such a manner that, when the mounting plate to which the solid-state imaging device is bonded, is fixed with a screw, the solid-state imaging device is positioned at a proper position relative to the photographing optical system. Accordingly, the positioning accuracy of the solid-state imaging device with respect to the photographing optical system depends upon how exact the solid-state imaging device is bonded in position on the mounting plate.
Conventionally, an opening having an appropriate shape, such as a circle, is formed in a mounting plate, and a positioning mark for positioning the solid-state imaging device is formed on a bonding surface to which the solid-state imaging device is bonded. The solid-state imaging device is placed on the bonding surface in such a manner that a rear surface of the solid-state imaging device closes the opening, and the solid-state imaging device package is then positioned according to the positioning mark on the mounting plate. After that, an appropriate adhesive agent is supplied to the opening, and dried so that the solid-state imaging device is fixed on the mounting plate.
When positioning a solid-state imaging device with respect to the photographing optical system of a digital camera or video camera, the light receiving area of the solid-state imaging device should be positioned in a proper position relative to the photographing optical system. However, the position of the light receiving area relative to a solid-state imaging device package is not uniform, but may be slightly different even in a device manufactured with the identical standards. Therefore, conventionally, even if the solid-state imaging device package is positioned according to the positioning mark, and bonded on the mounting plate, the light receiving area is not necessarily positioned correctly.
Thus, conventionally, when a mount plate, on which a solid-state imaging device is bonded, is fixed with a screw to an inner frame provided inside a digital camera or video camera, it is necessary to finely adjust the screwed position of the mounting plate within the range of play available between the hole of the mounting plate and the stem of the screw. Due to this, the operation of screwing the mounting plate to the inner frame inside the digital camera or video camera takes time, which makes the assembly cost of the digital camera or video camera expensive.
Further, in a conventional mounting plate, the shape of the opening is simple, such as circular, and when an adhesive agent is supplied to a simple-shaped opening to bond the solid-state imaging device to the mounting plate, the bonding takes place at the periphery of the circular opening, so that sufficient bonding strength cannot be obtained.